Article Citation: Holzer M, et al. “Mild Therapeutic Hypothermia to Improve the Neurologic Outcome After Cardiac Arrest”. The New England Journal of Medicine. 2002. 346(8):549-556.
What we already know about the topic: prelim studies demonstrated that lowering brain temp s/p cardiac arrest improves neurologic recovery.
Why this study is important: Hypoxemic brain injury is the most common cause of death in patients s/p cardiac arrest and lowering brain temperature reduces risk of neurologic injury.
Brief overview of the study:
- Study design: multicenter, unblinded RCT in 9 centers in 5 European countries from 1996-2000 with intention to treat
- N = 275
- Hypothermia n = 137
- Normothermia n = 138
- Patients were randomly assigned to hypothermia and normothermia groups.
- Hypothermia: target bladder temp 32-34 within 4h after ROSC with external cooling device and temp maintained for 24h from start of cooling followed by passive rewarming to temp > 36
- Neurologic outcome assessed using Pittsburgh cerebral performance scale:
1: good recovery
2: moderate disability
3: severe disability
4: vegetative state
1&2 = favorable outcome.
Primary outcome: favorable neurologic outcome within 6 months: 55% (hypothermia) vs 39% (normothermia)
Limitations: it was a small trial where physician were not blinded to treatment assignments.
Take home points: in pts with VF or pulseless VT arrest, mild therapeutic hypothermia (32-34 degree celcius) improved neurologic outcomes and reduced mortality at 6 months.
TTM trial in 2013 found no difference between temp targets of 33 and 36 for all cause mortality or cognitive benefit. So maybe avoiding hyperthermia is the key here?
Case summary: Thanks to Adam Tabbaa (double-double) for presenting a case of a 70M with PMH obesity presenting with LLE edema and dyspnea and found to have a PE that made our nerd-hearts sing!
- Anti-coag clinic pearl: for patients with a positive LE ultrasound OR CTPE, getting that second confirmatory imaging study (e.g. either CTPE or LE ultrasound) can seem like overkill. However, for providers who follow patients longitudinally, this additional imaging is useful (e.g. for serial imaging comparison, to monitor clot burden when considering whether to come off of anticoagulation)
- The most recent CHEST VTE guidelines recommend DOACs (e.g. apixaban) as FIRST LINE for DVT/PE over vitamin K antagonists except patients with cancer-associated thrombosis (though clinical trials are underway to test DOACs in cancer).
- Per a recent NEJM study, there is little benefit to screening for malignancy in unprovoked PE.
Why get an ultrasound in addition to a CTPE? Can be helpful for providers who follow patients longitudinally!
- Serial imaging comparison
- Helps when trying to get patients OFF anticoagulation (can follow serial U/S)
- Helps if patient has subsegmental PE on CTPE (if have a DVT, this supports anticoagulation)
No benefit to screening for malignancy with CT abdomen/pelvis in unprovoked PE
- 854 patients randomized to limited cancer screening (basic blood testing, chest radiography, and screening for breast, cervical, and prostate cancer) versus limited + CT A/P. There was no significant difference between the two study groups in the mean time to a cancer diagnosis (4.2 months in the limited-screening group and 4.0 months in the limited-screening-plus-CT group, P=0.88) or in cancer-related mortality (1.4% and 0.9%, P=0.75).
DOACs are FIRST LINE for DVT/PE!
- In AT10, the first-line recommended anticoagulant therapy includes dabigatran, rivaroxaban, apixaban, or edoxaban over vitamin K antagonists (VKA) or low molecular weight heparin (LMWH).
- The one exception is in patients with cancer-associated thrombosis. In this subset, AT10 recommends LMWH over VKA or DOACs with extended therapy.
PE Risk stratification
- Rely on vital signs, biochemical markers, TTE and imaging to risk stratify VTE patients.
- Note that degree of clot burden does not factor into risk stratification (as long as PE is segmental).
- Here is a nifty risk stratification algorithm.
Management of PE: An Update. J Am Coll Cardiol 2016;67;976-990.
Filed under: Morning Report